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Old 01-16-2007 | 04:26 AM
  #90  
Mosc_007
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Joined: Jan 2007
Posts: 130
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Originally Posted by Z-Mann
im going to try cell 6 again tonite as well as 1 & 3
it was supposed to be 20 amps as i changed to slot 2 so maybe thats it.
i have a 20 amp bulb discharger which i prefer using ,but it has blown globe.
i hardly ever use the super nova for a discharge tool,as someone mentioned that it would be inconsistant plus it gets hot then u have to wait for it to cool down b efore starting a charge
id rather use it only to charge with...... ive had no problems with this charger
since using it only to charge
yep slot 2 & 3 have bit the dust u were right
now im gonna have to every cell again using my old faithful bulb discharger
I am sorry but you cant use a BULB discharger to measure a cells capacity. The problem is the current in the cells will drop as it discharges. So it might be 20 amps on a fully charged cell but by the time it's half discharged the current will have dropped to maybe 18 amps. And when its near fully discharged the current will drop to about 12 amps. Because the current is not constant the calculated mAh based on Discharge time and current will be quite inaccurate.

You MUST use a constant current discharger to measure the cells capacity accuratly. Thats why I said to use the SuperNova as it's using as Constant discharge current. It will be 20 Amps at the start of discharge and it will also be 20 Amps at the end of discharge.

The SuperNova doesnt need to be cooled after discharging. The 3 fans in it quite easily keep it at a reasonable temperature.


Charles
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